From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 940FAC44507 for ; Thu, 16 Jul 2026 02:31:56 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 76B896B0095; Wed, 15 Jul 2026 22:31:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 742286B0096; Wed, 15 Jul 2026 22:31:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 633B86B0098; Wed, 15 Jul 2026 22:31:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 3D63E6B0095 for ; Wed, 15 Jul 2026 22:31:55 -0400 (EDT) Received: from smtpin20.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay08.hostedemail.com (Postfix) with ESMTP id AC7001403A5 for ; Thu, 16 Jul 2026 02:31:54 +0000 (UTC) X-FDA: 84993064548.20.FB07F88 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf09.hostedemail.com (Postfix) with ESMTP id 1301A140009 for ; Thu, 16 Jul 2026 02:31:52 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=arYbAtWK; spf=pass (imf09.hostedemail.com: domain of harry@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=harry@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1784169113; b=c09HJFaMjBD8VuXI5E8qcaFkKfwM0xwtD0n6TDY05yFCDLWM6PnhArXnromeiKZwH9nHtg NmmdYaWd/7ZzsoIo7ohZvbOkP95EXrPu6XZOVgDiLy4nLouPvvZK+AGg/TTU0+Kvw2Qf1N nkItEQxx2gqEGANhth+CMWR/YKKrTYE= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=arYbAtWK; spf=pass (imf09.hostedemail.com: domain of harry@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=harry@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1784169113; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ynGIyMuoCcAD8NaeJqodKE7wCOdyZZLepombpmz0j20=; b=oWxWNkOvTJVgTssH+4gOJo9sUZ236RNRfUcOCsc3GzNT78n9BhiXAq0ALYbUdrj9dQqHDw 8XQFfYNQSMzzt1OLIw+iCOQPuxmTfgCSBDpizY5Bc+5rKyx4YmpURpmWDodKlUGBQoGBFI zW1n9aIF+Jq0z7+/rcSAlf2pSBPlt58= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 831CE6001A; Thu, 16 Jul 2026 02:31:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DCADC1F000E9; Thu, 16 Jul 2026 02:31:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784169112; bh=ynGIyMuoCcAD8NaeJqodKE7wCOdyZZLepombpmz0j20=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=arYbAtWK4LRZHodP80tz03WZeyNNdKPJq+lxECSV5GryUBNFR5Gk4F6+APA2CQnOb 08c5nJ7fZJCbIMppyZmV/AqhU5CfENRjMb9CqkND87C9YH+JPlEafl1lhYR23Le9dW d7zZYG6LcET4EoWG/1qg2n9J9np9e++xKP6F6sxNRxGqDwRulzu0s16W676NdNWQ5N qAIwZNqBZnfQ1X+GoYYhmmmEt/I44c+WNrchLy/Mm7RlGEXSNHLSkJY78+XhmOflSy EbUXzEig/dVOJvqrLh+J3egH77K1PgPo2mzv8evsi+pBbV5b/rbLkhzFWLL8bF6V03 q9GVYEU79wMAQ== Message-ID: <093c6dbe-6ca3-47cd-bf8d-3cc85c13f7ac@kernel.org> Date: Thu, 16 Jul 2026 11:31:45 +0900 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH slab/for-next-fixes v3 1/4] mm/slab: fix a memory leak due to bootstrapping sheaves twice To: Suren Baghdasaryan Cc: Vlastimil Babka , Andrew Morton , Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , "Liam R. Howlett" , Hao Ge , Kees Cook , Pedro Falcato , Shakeel Butt , Danielle Constantino , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260713-kmalloc-no-objext-v3-0-47c7bd138de7@kernel.org> <20260713-kmalloc-no-objext-v3-1-47c7bd138de7@kernel.org> Content-Language: en-US From: Harry Yoo In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------fEYtHpWT6oe3c0X3dvhfUDl0" X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 1301A140009 X-Stat-Signature: iy9bqdh3i6f8cjafjwr4dmbw8ap9u9ba X-HE-Tag: 1784169112-430879 X-HE-Meta: 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 6or3XQly 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --------------fEYtHpWT6oe3c0X3dvhfUDl0 Content-Type: multipart/mixed; boundary="------------vbeyTvd6sxOFnT8cjLtWNjuj"; protected-headers="v1" From: Harry Yoo To: Suren Baghdasaryan Cc: Vlastimil Babka , Andrew Morton , Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , "Liam R. Howlett" , Hao Ge , Kees Cook , Pedro Falcato , Shakeel Butt , Danielle Constantino , linux-mm@kvack.org, linux-kernel@vger.kernel.org Message-ID: <093c6dbe-6ca3-47cd-bf8d-3cc85c13f7ac@kernel.org> Subject: Re: [PATCH slab/for-next-fixes v3 1/4] mm/slab: fix a memory leak due to bootstrapping sheaves twice References: <20260713-kmalloc-no-objext-v3-0-47c7bd138de7@kernel.org> <20260713-kmalloc-no-objext-v3-1-47c7bd138de7@kernel.org> In-Reply-To: --------------vbeyTvd6sxOFnT8cjLtWNjuj Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 7/14/26 12:30 AM, Suren Baghdasaryan wrote: > On Mon, Jul 13, 2026 at 7:29=E2=80=AFAM Harry Yoo (Oracle) wrote: >> >> When kmalloc caches are aliased, multiple cache pointers reference >> the same kmem_cache. As a result, iterating over kmalloc indices and >> bootstrapping sheaves can bootstrap the same cache more than once and >> leak memory. >> >> Currently, this could happen when the architecture specifies >> minimum alignment for slab caches that is larger than >> ARCH_KMALLOC_MINALIGN. >> >> Bootstrap sheaves only when the cache does not have them already. >> Add a warning when bootstrap_cache_sheaves() is called for a cache >> that already has sheaves enabled. >> >> Cc: stable@vger.kernel.org >> Fixes: 913ffd3a1bf5 ("slab: handle kmalloc sheaves bootstrap") >> Signed-off-by: Harry Yoo (Oracle) >=20 > nit: Don't know if we really need a warning... Hehe, at least the warning allowed me to confirm that this is not an oversight and the patch fixed it :) > I would just do an > early return from bootstrap_cache_sheaves() if cache_has_sheaves() is > true. But that's not critical. But yeah, no strong opinion on this. > Reviewed-by: Suren Baghdasaryan Thanks! --=20 Cheers, Harry / Hyeonggon --------------vbeyTvd6sxOFnT8cjLtWNjuj-- --------------fEYtHpWT6oe3c0X3dvhfUDl0 Content-Type: application/pgp-signature; name="OpenPGP_signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="OpenPGP_signature.asc" -----BEGIN PGP SIGNATURE----- iHUEARYKAB0WIQQQ1ub6gR5ogjaKRmOGXBN6rc5S1gUCalhCkQAKCRCGXBN6rc5S 1nsaAQCpaAuH8Gtt1L7sSRp6NLtXdS3rymXJGVx8TEl7PzJAMQD/f0VpUHt3Q/Xa GgIaG4fD6fiQReheoPjiIEKi+SYxpQ4= =y4X0 -----END PGP SIGNATURE----- --------------fEYtHpWT6oe3c0X3dvhfUDl0--